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The exploration of new and efficient energy storage mechanisms through nanostructured electrode design is crucial for the development of high‐performance rechargeable batteries. Herein, black phosphorus quantum dots (BPQDs) and Ti3C2 nanosheets (TNSs) are employed as battery and pseudocapacitive components, respectively, to construct BPQD/TNS composite anodes with a novel battery‐capacitive dual‐model energy storage (DMES) mechanism for lithium‐ion and sodium‐ion batteries. Specifically, as a battery‐type component, BPQDs anchored on the TNSs are endowed with improved conductivity and relieved stress upon cycling, enabling a high‐capacity and stable energy storage. Meanwhile, the pseudocapacitive TNS component with further atomic charge polarization induced by POTi interfacial bonds between the two components allows enhanced charge adsorption and efficient interfacial electron transfer, contributing a higher pseudocapacitive value and fast energy storage. The DMES mechanism is evidenced by substantial characterizations of X‐ray photoelectron spectroscopy and X‐ray absorption fine structure spectroscopy, density functional theory calculations, and kinetics analyses. Consequently, the composite electrode exhibits superior battery performance, especially for lithium storage, such as high capacity (910 mAh g−1 at 100 mA g−1), long cycling stability (2400 cycles with a capacity retention over 100%), and high rate capability, representing the best comprehensive battery performance in BP‐based anodes to date.

Exploring Si-based anode materials with high electrical conductivity and electrode stability is crucial for high-performance lithium-ion batteries (LIBs). Herein, we propose the fabrication of a Si-based composite where Si porous nanospheres (Si p-NSs) are tightly wrapped by Ti 3 C 2 T x (T x stands for the surface groups such as −OH, −F) MXene nanosheets (TNSs) through an interfacial assembly strategy. The TNSs as a conductive and robust tight of the Si p-NSs can effectively improve electron transport and electrode stability, as revealed by substantial characterizations and mechanical simulations. Moreover, the TNSs with rich surface groups enable strong interfacial interactions with the Si p-NS component and a pseudocapacitive behavior, beneficial for fast and stable lithium storage. Consequently, the Si p-NS@TNSs electrode with a high Si content of 85.6% exhibits significantly enhanced battery performance compared with the Si p-NSs electrode such as high reversible capacity (1154 mAh g −1 at 0.2 A g −1 ), long cycling stability (up to 2000 cycles with a 0.026% capacity decay rate per cycle), and excellent rate performances. Notably, the Si p-NS@TNSs electrode-based LIB full cell delivers a high energy uptake of 405 Wh kg −1 , many-times higher than that of the Si p-NSs full cell. This work offers a strategy to develop advanced Si-based anode materials with desirable properties for high-performance LIBs.

The intercalation strategy has become crucial for 2D layered materials to achieve desirable properties, however, the intercalated guests are often limited to metal ions or small molecules. Here, we develop a simple, mild and efficient polymer-direct-intercalation strategy that different polymers (polyethyleneimine and polyethylene glycol) can directly intercalate into the MoS2 interlayers, forming MoS2-polymer composites and interlayer-expanded MoS2/carbon heteroaerogels after carbonization. The polymer-direct-intercalation behavior has been investigated by substantial characterizations and molecular dynamic calculations. The resulting composite heteroaerogels possess 3D conductive MoS2/C frameworks, expanded MoS2 interlayers (0.98 nm), high MoS2 contents (up to 74%) and high Mo valence (+6), beneficial to fast and stable charge transport and enhanced pseudocapacitive energy storage. Consequently, the typical MoS2/N-doped carbon heteroaerogels exhibit outstanding supercapacitor performance, such as ultrahigh capacitance, remarkable rate capability and excellent cycling stability. This study offers a new intercalation strategy which may be generally applicable to 2D materials for promising energy applications.

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electric grids, as well as biocompatible technologies, has attracted tremendous attention and is still a big challenge in the energy field. [1-4] The electrochemical energy storage and conversion devices, such as rechargeable batteries, supercapacitors, fuel cells, and electrolyzers, have been extensively explored. It is well known that electrode materials, e.g., anodes, cathodes, and catalysts, are the heart components of these devices, which play a decisive role in determining performance. Mesoporous materials, which have pore sizes ranging from 2 to 50 nm defined by the International Union of Pure and Applied Chemistry, possess exceptional features, including high specific surface areas, large pore volumes, tunable pore sizes, and controllable geometries (Figure 1a-c). These features enable mesoporous materials as ideal candidates for energy conversion and storage because of the increased active reaction sites and enhanced transport efficiency of reactants. [3,5-7] Therefore, many precise manipulations and structural engineering strategies have been applied to construct advanced mesoporous electrodes with excellent electrochemical performance. Besides, the achieved electrodes with well-controlled mesoporous architectures could be used as platforms to study the fundamental research about the mass transport kinetics, charge transfer, and storage mechanism, as well as the interface electrochemical reactions behavior under the mesoporous nanoconfined space (Figure 1d-g). These fundamental studies are of great importance for further guiding the design of high-performance mesoporous electrodes for electrochemical energy storage and conversion. [6,8,9] In this Essay, we introduce the methods for synthesizing different types of mesoporous materials. Also, the key developments of applications of mesoporous materials in electrochemical energy conversion and storage devices are highlighted. The synthesis-structure-property of mesoporous materials and their applications in rechargeable batteries, supercapacitors, fuel cells, and electrolyzers have been detailed, providing creative insight and enlightening comments on the construction of high-performance mesoporous electrodes. Following these, we propose the research challenges and perspectives on mesoporous materials for the future development of energy conversion and storage devices. Developing high-performance electrode materials is an urgent requirement for next-generation energy conversion and storage systems. Due to the exceptional features, mesoporous materials have shown great potential to achieve high-performance electrodes with high energy/power density, long lifetime, increased interfacial reaction activity, and enhanced kinetics. In this Essay, applications of mesoporous materials are reviewed in electrochemical energy conversion and storage devices. The synthesis, structure, and properties of mesoporous materials and their performance in rechargeable batteries, supercapacitors, fuel cells, and electrolyzers are discussed, providing practical details and enligh...

The exploration of ideal electrode materials overcoming the critical problems of large electrode volume changes and sluggish redox kinetics induced by large ionic radius of Na+/K+ ions is highly desirable for sodium/potassium‐ion batteries (SIBs/PIBs) toward large‐scale applications. The present work demonstrates that single‐phase ternary cobalt phosphoselenide (CoPSe) in the form of nanoparticles embedded in a layered metal–organic framework (MOF)‐derived N‐doped carbon matrix (CoPSe/NC) represents an ultrastable and high‐rate anode material for SIBs/PIBs. The CoPSe/NC is fabricated by using the MOF as both a template and precursor, coupled with in situ synchronous phosphorization/selenization reactions. The CoPSe anode holds a set of intrinsic merits such as lower mechanical stress, enhanced reaction kinetics, as well as higher theoretical capacity and lower discharge voltage relative to its counterpart of CoSe2, and suppressed shuttle effect with higher intrinsic electrical conductivity relative to CoPS. The involved mechanisms are evidenced by substantial characterizations and density functional theory (DFT) calculations. Consequently, the CoPSe/NC anode shows an outstanding long‐cycle stability and rate performance for SIBs and PIBs. Moreover, the CoPSe/NC‐based Na‐ion full cell can achieve a higher energy density of 274 Wh kg−1, surpassing that based on CoSe2/NC and most state‐of‐the‐art Na‐ion full cells based on P‐, Se‐, or S‐containing binary/ternary anodes to date.